<!doctype html>
<html>
 <head>
 <meta charset="utf-8">
 <title>Fountain</title>
 <link rel="stylesheet" href="style.css">
 </head>
 <body>
 <canvas id="canvas" width="400" height="400"></canvas>
 <script src="utils.js"></script>
 <script src="ball.js"></script>
 <script>
 window.onload = function () {
 var canvas = document.getElementById('canvas'),
 context = canvas.getContext('2d'),
 balls = [],
 numBalls = 80,
 gravity = 0.5;
 for (var ball, i = 0; i < numBalls; i++) {
	 ball = new Ball(2, Math.random() * 0xffffff);
	 ball.x = canvas.width / 2;
	 ball.y = canvas.height;
	 ball.vx = Math.random() * 2 - 1;
	 ball.vy = Math.random() * -10 - 10;
	 balls.push(ball);
 }
 function draw (ball) {
	 ball.vy += gravity;
	 ball.x += ball.vx;
	 ball.y += ball.vy;
	 if (ball.x - ball.radius > canvas.width ||
	 ball.x + ball.radius < 0 ||
	 ball.y - ball.radius > canvas.height ||
	 ball.y + ball.radius < 0) {
		 ball.x = canvas.width / 2;
		 ball.y = canvas.height;
		 ball.vx = Math.random() * 2 - 1;
		 ball.vy = Math.random() * -10 - 10;
	 }
	ball.draw(context);
 }
 (function drawFrame () {
	 window.requestAnimationFrame(drawFrame, canvas);
	 context.clearRect(0, 0, canvas.width, canvas.height);
	 balls.forEach(draw);
 }());
 };
 </script>
 </body>
</html>